Added "--login-user=" option for the Guest session.

chrome/browser/sessions/session_restore.cc

Index: chrome/browser/sessions/session_restore.cc
diff --git a/chrome/browser/sessions/session_restore.cc b/chrome/browser/sessions/session_restore.cc
index 480f80f714e22025c2ea6d60d6127617258d70c9..8525d9744c03171a5b31d6d4828f3213cd42e264 100644
--- a/chrome/browser/sessions/session_restore.cc
+++ b/chrome/browser/sessions/session_restore.cc
@@ -652,10 +652,8 @@ class SessionRestoreImpl : public NotificationObserver {
 
     // Record an app launch, if applicable.
     GURL url = tab.navigations.at(tab.current_navigation_index).virtual_url();
-    // TODO: the ExtensionService should never be NULL, but in some cases it is,
-    // see bug 73768. After it is resolved, the explicit test can go away.
-    ExtensionService* service = browser->profile()->GetExtensionService();
-    if (service && service->IsInstalledApp(url)) {
+    DCHECK(browser->profile()->GetExtensionService());
+    if (browser->profile()->GetExtensionService()->IsInstalledApp(url)) {
       UMA_HISTOGRAM_ENUMERATION(extension_misc::kAppLaunchHistogram,
                                 extension_misc::APP_LAUNCH_SESSION_RESTORE,
                                 extension_misc::APP_LAUNCH_BUCKET_BOUNDARY);